I would like to thank the guys at sickbikeparts for producing a product that works very well on these motorized bikes. They are innovators that keep bringing us improvements to our bikes. I have run into a few issues with my install and my kit has 200 miles on it.

When I am in high gear I am noticing some chain slip between the "pedal" chain and the highest gear in the rear cassette. Im not sure whether this is a chain line issue caused by the front freewheel system supplied by the kit (it isnt because of my chain since the problem has occured on the original chain and a brand new one and it is not because the rear cassette is too worn since I have tried two different cassettes with the same result.)

The directions in the kit state that the chain supplied will stretch and the person installing the kit will need to adjust the engine position about 3 times until it fully seats. I have adjusted my engine at least six times and the engine hasnt slipped down the frame. How do I know? I welded the bracket to the frame to eliminate that as a possible reason for so much chain slop. As it stands now I cannot move the engine any higher in the frame. I began searching for other locations that would cause the excess slack in the chain. I then noticed that the right hand bracket supplied by the kit was warped and the right side bearing was trashed. My only possible explanation for this occurence would be the higher amount of power my engine is producing. I can not allow the extra slack in the chain because it will derail within a short time which in turn derails the pedal chain which then gets wrapped up around the bottom bracket and jammed underneath the nuts securing the front chainring.

I wrote this to hopefully determine what is causing these issues and what possible solutions are available. I already plan to reinforce the right side bracket and I have also purchased new bearings. I dont know if this will be corrected in future revisions. I just need my bike to be reliable. Im not posting this to deter anyone from purchasing this kit since I have had a lot of fun with this kit and it is of high quality. Thanks Sickbikeparts !! -Justin

Sorry for the bad photos. The bracket was bent a little more severe before because I tried to bend it straight again and spot welded the bearing in place just to try to see what was goin on with the plate... You can see how slack the chain is from the bend in the plate...

wow, how did you manage that one? Is your motor really producing that much more power? (if so, HOW) Or could it be from a misalignment of the plates causing the jackshaft to not run perpendicular to the side of the motor?

no idea but i know i followed all of the directions and made sure that the plate was perpendicular to the engine... and both plates were parrallel... The only thing i didnt do was install one washer under one bolt on that plate but the bend in the plate is about 1.5" away from that bolt so i dont think thats the problem. The aluminum bracket is installed too. I think I will weld some extra steel to the area once it is again straight...

I was gonna get one these jack shaft kits, but the latest posts I've read is making me rethink about this product, its seems that there going to have to make a some major modifications on this kit. Im sure there is workable solution to problems encountered with chain wear causing to much slack etc but as far as I can tell it seems for now I'll be holding back on getting one and keep my vibrating single speed situation.

If you install the kit exactly as the instructions say, you should have no issues. Sure, the chain may loosen a bit, so you tighten it. After the 2nd time retightening, I haven't had an issue since. (they also have a tensioner available) [and the stock HT chain likes to loosen a LOT, so that has to be tightened normally till it's broken in, so that would be nothing new]

I think europorsche's situation is a unique one, and I honestly wouldn't worry about this happening to you. The kit is well worth the money and is a nice piece of gear. Just take your time and install it properly and you should be good to go.

I was gonna get one these jack shaft kits, but the latest posts I've read is making me rethink about this product, its seems that there going to have to make a some major modifications on this kit. Im sure there is workable solution to problems encountered with chain wear causing to much slack etc but as far as I can tell it seems for now I'll be holding back on getting one and keep my vibrating single speed situation.

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Allow me to kindly address your concerns.

I can for one assure you that no "major modifications" are needed. I can also, absolutely assure you that chain wear is not causing "to (sic) much slack etc". We have a very simple solution for folks with a slack chain issue: Chain Adjuster and for dialing in the perfect chain length: 1/2Link. Folks do need to know if the engine can move, the chain will get some slack. Other than that we have 100's of happy customers, with zero issues. Thanks!

I have been watching, very closely, the progress of SBP's shifter kit. From all the threads that I have seen about their kit, I, personally, am very surprised there hasn't been more problems. The very few threads I have seen, where people had a problem, SBP, members of this board, have stepped right up and been very helpful, willing to do what they need to in order to help the customer.

hey jasonh I just now watched your little video. Not once did I hear you shift, the engine made the same single speed drone that all bikes make, so where's the shift kit?? Or was this video made prior to your installation of said jackshaft kit? I would run a get that thing right away, but I guess you hav'nt read any of the guys having to reposition the engine 6 times. Another saying that the structural part side plates twisted, you may have had no problems but this guy states he's looking to commute and not encounter all the adjustments he had to do.

That video was done a long time ago before I had the shift kit. I have not made a video recently.

As for the "adjusting the engine 6 times" thing, that's what SBP makes the tensioner for - you won't have to adjust your motor again. I had to adjust mine twice to get the chain to keep the correct tension. Some people may have to do it more, some less. it all depends on the frame, your mounts, how tight you get them, etc.

The side plate twisting, I'm willing to bet it is due to installing in a non-standard way.

My bike is built as a commuter as well. I don't currently use it to commute as it's usually 20 degrees or so in the morning, but once it warms up I will. I'm taking the time currently to get all the bugs worked out BEFORE I use it as a commuter.

ALL the problems with this kit I have seen posted publicly have been due to a non-standard installation. If you take your time and install in the suggested manner, I don't think you'll have an issue. And somehow if you do end up with an issue due to a faulty part, SBP will take care of you.

SBP has been great about their products and support. I will gladly stand proud in support of what they're doing.

Pablo actually predicted a problem i would have before it even happened! The reason? i was being stupid and impatient. My fault, not the kit. As it happened a bit of know how and luck with my drilling means i have a fantastic bit of kit. A truly worthwhile investment in my eyes.

As far as tweaking and modifications go, if you look at the big picture, we are talking about a chain. A chain, thats all. Think of all the head and heartaches your first engine fitting caused on its own!?
Compared to that this kit is a breeze, with logical, clear and well thought out instructions.

Aside from the shifting advantage, this kit, by taking away the need for a secondary chain, makes tyre changing/replacing as simple as a normal bike. No farting around popping masterlinks and seemingly endless micro adjusting of chain tensioners!

Anyone who delays their purchase of a shifter kit based on "fears of adjustments" shouldn't even have a motored bike to begin with! - Well, thats my thought anyhoo.

Are these gas bikes doing well in England and your opinion do think they will be a commercial success? Your country and the rest of Europe has endured extremely high petrol prices, I would think that this would be great alternative to getting around at fraction of the cost. I do not think however that your that your comments are significant when you speak about this jackshaft.
First off their are several complaints about their inability to perform as intended. Many people will not venture to try it cause its a relatively new idea, and the only ones I believe that will try it would be guys with extensive mechanical background.

On the internet it is very difficult to separate the cobblers from those with mechanical aptitude. On the internet the worst of the cobblers can appear to be a mechanical genius to the unknowing masses.

Until you have actually installed one of the shifter kits...it is asinine to post an opinion or relay info from cobblers about SBP's product. I can guarantee you without a doubt that not one mechanically inclined biker has had a complaint about this kit!

milegajo is right! These bikes are assembled by us, (the non-cobblers), they are not manufactured as complete units for the benefit of providing instant gratification. If you are unable to do it...leave it at that....and stop interjecting!

Basic mechanical ability is required to install the Chinese kit...The guys at SBP have done a far superior job in terms of quality and documentation than any of the Chinese, "engine kit", factories could ever hope to accomplish.

I have had a 2% failure rate so far with my clutch kits, and I consider that excellent considering the application.

SBP has an excellent record of both overall product satisfaction and customer service/support.